8 Responses. > 1  the Moon takes an elliptical path around the Earth. The planets make nearly elliptical orbits around the Sun, close enough for reasonable approximations, but the Moonâs Orbit around the Earth is sufficiently influenced by the Sun that it follows a path detectably different from an ellipse.
Quick Answer. In 1896, French scientist Antoine Henri Becquerel discovered radioactivity which was an early contribution to atomic theory. He discovered this phenomenon while experimenting with uranium and a photographic plate. Continue Reading.
Relevance. Rating Newest Oldest. Best Answer: Niels Bohr put forward his picture of the atom in 1913. He used Max Plank's quantum theory and suggested that electrons can have only certain amounts of energy, and their orbit can have onlt certain radii and that the electrons which absorb photons move to higher orbits.